Fully automatic firearm rounds must be those ones that shoot themselves.
Fully automatic rounds are belt linked rounds for use in a belt fed weapon such as a M249 or M240 being 5.56 mm and 7.62mm respectively as opposed to bulk ammo that is loaded in magazines for use in box fed rifles or magazine fed pistols. The U.S. Military also inventories ammo this way with separate line items for belts of ammo vs bulk boxes. There is also an exception made for special 9mm rounds that meet the NATO SMG standard which cannot be used in any weapon but a 9mm sub machine gun because they are loaded to much higher chamber pressures than would be safe in a blowback pistol.